Aqueduto das Águas Livres and Mãe d'Água

The Aqueduto das Águas Livres (the “Free Waters” aqueduct) is the long line of stone arches you see striding across the Alcântara valley as you drive into Lisbon from the west. It was built between 1731 and 1799 by royal decree to bring spring water into the city, and it works entirely by gravity: the channel slopes gently downhill all the way, so the water flows without a single pump.

The section over the Alcântara valley is the part families visit. It has 35 arches spread over 941 metres, and the biggest is, according to EPAL, the largest pointed stone arch in the world: 65.29 metres high and 28.86 metres wide. The aqueduct is part of EPAL’s Water Museum, and the entrance for the walk is at Calçada da Quintinha 6 in Campolide.

On a self-guided visit you walk along the top of the arcade, with the valley, the motorway and the city spread out below. For a child who likes heights, that is the thrill. You are a very long way up, so hold small hands and keep an eye on climbers.

A few facts that tend to stick with children:

• The aqueduct was paid for by a special tax called the Real de Água, charged on everyday things like olive oil, wine and meat. Everyone in the city chipped in, whether they liked it or not.
• It survived the great earthquake of 1755, which destroyed much of Lisbon. The arches were still standing afterwards.
• The main line runs about 14 km, from the Mãe de Água Velha spring in Belas to the Mãe d’Água reservoir at Amoreiras. By the mid-19th century the whole network of branches and galleries reached about 58 km and fed around 60 fountains.
• About 12 km of the system runs underground in five galleries, spreading out under the western half of the city to public fountains.
• People stopped drinking its water in the 1960s. It has been a National Monument since 1910.

Older children may already have heard of Diogo Alves, a 19th-century criminal whose crimes on the aqueduct are part of Lisbon folklore. EPAL covers the story in its podcast, so you can decide whether your child is ready for it before you go.

At the city end of the aqueduct is the Reservatório da Mãe d’Água das Amoreiras, on Praça das Amoreiras. Hungarian architect Carlos Mardel began it in 1746. Work stalled after his death in 1763, resumed in 1771 under Reinaldo Manuel dos Santos, and the roof was only finished in 1834, under Queen Maria II.

Inside it feels like a church. Water pours from a dolphin-shaped spout down a cascade built from stones brought from the aqueduct’s springs, into a tank seven and a half metres deep that holds 5,500 cubic metres. Four sturdy square pillars hold up a vaulted ceiling, and on top of that ceiling is a panoramic terrace looking out over Lisbon. Beside the reservoir, the Casa do Registo (the “register house”) was where staff controlled how much water went to each fountain, factory, convent and noble house. The reservoir also hosts exhibitions.

The Water Museum runs a busy programme of guided routes, many of them underground. These are the ones listed for 2026 that children can join. All are for ages 6 and up unless noted, and tickets are sold through Ticketline:

• A one-hour guided walk over the aqueduct arches, €6, from Calçada da Quintinha 6.
• A one-hour tour of the Galeria Subterrânea do Loreto, an underground water gallery, €6.
• “O Aqueduto de Lisboa”, a 180-minute tour covering about 3.5 km, much of it underground, €18. Dates in 2026 ran from January to March.
• “Lisboa Subterrânea”, 180 minutes through two reservoirs and an underground gallery, €12.
• “Águas Secretas de Lisboa”, 120 minutes, €12.
• “O Aqueduto Secreto de Campo de Ourique”, 120 minutes, for ages 8 and up, €10, which goes inside the Duarte Pacheco viaduct.
• “Fora d’Horas no Aqueduto”, a one-hour sunset visit to the arches for ages 4 and up, €6, with dates to be announced.
• “Mistérios de Monsanto”, 180 minutes from the aqueduct into Monsanto Forest Park and the Fronteira Palace gardens, €18, dates to be announced.

On the European Heritage Days (25 and 26 September in 2026) the museum ran a free two-hour “Lisboa 360º” walk for all ages across the aqueduct to the Mãe d’Água terrace, booked by phone.

EPAL warns that the underground tours are not suitable for anyone with claustrophobia or limited mobility, and asks for closed, comfortable, waterproof shoes. Many of the 2026 dates fell in the first half of the year, so check the agenda page for the next season.

Under-18s go free at all Water Museum sites. When we checked, adults paid €4 for the aqueduct and €4 for the Mãe d’Água on a self-guided visit, with 50% off for students, over-65s and Lisboa Card holders. Everyone gets in free on the first Sunday of the month and on six set days: 22 March, 18 April, 18 May, 1 June, 5 June and 1 October.

Both sites open Tuesday to Sunday, 10:00 to 18:00, and close on Mondays and on 1 January, 1 May and 25 December. The aqueduct entrance is served by buses 742, 751 and 758. The Mãe d’Água is a short walk from Rato metro station (yellow line), or buses 706, 709, 711, 727, 738 and 758.

The two sites are about 2 km apart. EPAL’s pages do not mention cafés or parking at either one, so plan food around the Amoreiras and Rato area.

Children who like big views, bridges or anything about how things were built will love the walk over the arches. The Mãe d’Água suits calmer children: it is cool, echoey and quiet, and the cascade is mesmerising.

A child who is frightened of heights may not enjoy the arches at all, so talk about it first. The arches are exposed to sun and wind, with no shade on top, so bring hats and water in summer. The underground tours are long (up to three hours) and not for anyone who dislikes tight, dark spaces. Toddlers can do the self-guided arch walk in a carrier, but the organised tours start at age 4 or 6.

The steam pumping station at Museu da Água Barbadinhos is the next chapter of the same story, when a second aqueduct and steam engines took over in 1880. From the aqueduct end, Parque Florestal de Monsanto is close by for a picnic and a run. Pilar 7, inside a pillar of the 25 de Abril bridge, is another engineering visit down in Alcântara.

Can you walk on the Lisbon aqueduct?

Yes. The self-guided visit takes you along the top of the arches over the Alcântara valley, entering from Calçada da Quintinha 6 in Campolide. It is open Tuesday to Sunday, 10:00 to 18:00.

How much does it cost?

Under-18s go free. When we checked in September 2026, adults paid €4 for the aqueduct and €4 for the Mãe d’Água, with free entry for everyone on the first Sunday of the month.

Is the aqueduct walk safe for small children?

The walk is very high and exposed to sun and wind. Keep toddlers in a carrier or holding hands, and skip it if your child is scared of heights.

Can you take a buggy?

EPAL does not publish accessibility details for the walk, and the underground tours are not suitable for anyone with limited mobility. A carrier is the safer choice.

How old do children need to be for the underground tours?

Most are for ages 6 and up, a few for ages 8 and up, and the sunset visit for ages 4 and up. Book through Ticketline.